{"id":"CVE-2026-128342","aliases":[],"cve":{"records":[{"id":"CVE-2026-128342","source":"VulnCheck","state":"PUBLISHED","reasons":[],"replacements":[],"disputed":false,"unsupportedWhenAssigned":false,"reserved":"2026-11-13T01:20:41.765Z","published":"2026-11-13T09:33:34.387Z","modified":"2026-11-13T09:33:34.387Z"}],"publishers":[{"name":"VulnCheck","role":"CNA","organizationId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","modified":"2026-11-13T09:33:34.387Z"}],"references":[{"url":"https://github.com/exceljs/exceljs","tags":["product"],"source":"VulnCheck"},{"url":"https://github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-9vv6-5g3h-prg5","tags":["third-party-advisory"],"source":"VulnCheck"},{"url":"https://github.com/exceljs/exceljs/blob/v4.4.0/lib/doc/workbook.js#L200-L206","tags":["technical-description"],"source":"VulnCheck"},{"url":"https://github.com/exceljs/exceljs/blob/v4.4.0/lib/doc/workbook.js#L119-L125","tags":["technical-description"],"source":"VulnCheck"},{"url":"https://www.vulncheck.com/advisories/exceljs-through-4.4.0-denial-of-service-via-oversized-worksheet-sheetid","tags":["third-party-advisory"],"source":"VulnCheck"}],"weaknesses":[{"id":"CWE-606","description":"Unchecked Input for Loop Condition","source":"VulnCheck"}],"applicability":[{"source":"VulnCheck","statements":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:exceljs_project:exceljs:*:*:*:*:*:*:*:*","versionEndIncluding":"4.4.0"}]}]}]}],"prioritization":[]},"title":"ExcelJS through 4.4.0 Denial of Service via Oversized Worksheet sheetId","titleSource":"VulnCheck","descriptionSource":"VulnCheck","description":"ExcelJS through 4.4.0 contains a denial of service vulnerability that allows attackers to block the event loop by supplying an unbounded sheetId in xl/workbook.xml. Attackers can provide a workbook with a huge sheetId, making the sparse worksheet array walk stall worksheets, getWorksheet and writeBuffer for seconds.","score":8.7,"severity":"high","published":"2026-11-13T09:33:34.387Z","modified":"2026-11-13T09:33:34.387Z","withdrawn":false,"knownExploited":false,"affected":[],"products":[{"vendor":"exceljs","name":"exceljs","platforms":[],"versions":[{"version":"0","status":"affected","lessThanOrEqual":"4.4.0","versionType":"semver"}],"defaultStatus":"unaffected","packageURL":"pkg:npm/exceljs","packageIdentity":{"ecosystem":"npm","name":"exceljs"},"cpes":[],"source":"VulnCheck","url":"https://www.cve.org/CVERecord?id=CVE-2026-128342"}],"remediation":[],"references":["https://github.com/exceljs/exceljs","https://github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-9vv6-5g3h-prg5","https://github.com/exceljs/exceljs/blob/v4.4.0/lib/doc/workbook.js#L200-L206","https://github.com/exceljs/exceljs/blob/v4.4.0/lib/doc/workbook.js#L119-L125","https://www.vulncheck.com/advisories/exceljs-through-4.4.0-denial-of-service-via-oversized-worksheet-sheetid"],"sources":[{"name":"CVE","id":"CVE-2026-128342","modified":"2026-11-13T09:33:34.387Z","url":"https://www.cve.org/CVERecord?id=CVE-2026-128342"}],"assessments":[{"source":"VulnCheck","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":8.7},{"source":"VulnCheck","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5}],"sourceAffected":[],"observedAt":"2026-11-13T17:58:13.080Z","kev":{"status":"not-listed","checkedAt":"2026-11-15T00:15:33.603Z"},"coverage":[{"source":"NVD","status":"refresh-failed","attemptedAt":"2026-11-14T09:10:34.418Z"},{"source":"GHSA","status":"available","checkedAt":"2026-11-14T09:05:32.907Z","attemptedAt":"2026-11-14T09:05:32.907Z"},{"source":"EUVD","status":"available","checkedAt":"2026-11-14T08:55:31.438Z","attemptedAt":"2026-11-14T08:55:31.438Z"},{"source":"EPSS","status":"available","checkedAt":"2026-11-14T08:55:31.329Z","attemptedAt":"2026-11-14T08:55:31.329Z"}],"evidence":[{"source":"FIRST EPSS","id":"CVE-2026-128342","url":"https://www.first.org/epss/","probability":0.0063,"percentile":0.50744,"date":"2026-11-13","checkedAt":"2026-11-14T08:55:31.329Z"},{"source":"ENISA EUVD","id":"EUVD-2026-125157","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-125157","modified":"Nov 13, 2026, 9:33:34 AM","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","checkedAt":"2026-11-14T08:55:31.438Z"},{"source":"GitHub Advisory Database","id":"GHSA-qwf5-f797-39mm","url":"https://github.com/advisories/GHSA-qwf5-f797-39mm","modified":"2026-11-13T12:31:42Z","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","checkedAt":"2026-11-14T09:05:32.907Z"}],"aiSummary":{"text":"ExcelJS through 4.4.0 has a denial of service vulnerability via oversized worksheet sheetId, allowing attackers to block the event loop. Attackers can provide a workbook with a huge sheetId. The impact is a stall of worksheets for seconds.","model":"@cf/meta/llama-3.3-70b-instruct-fp8-fast","generatedAt":"2026-11-14T03:36:01.330Z","sources":[{"name":"CVE","url":"https://www.cve.org/CVERecord?id=CVE-2026-128342"}]}}